[FFmpeg-devel] [PATCH] libavfilter: Add interlace detect filter.

Nicolas George nicolas.george at normalesup.org
Wed Apr 4 15:18:33 CEST 2012


Hi.

Le quintidi 15 germinal, an CCXX, Michael Niedermayer a écrit :
> Signed-off-by: Michael Niedermayer <michaelni at gmx.at>
> ---
>  libavfilter/Makefile     |    1 +
>  libavfilter/allfilters.c |    1 +
>  libavfilter/vf_idet.c    |  276 ++++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 278 insertions(+), 0 deletions(-)
>  create mode 100644 libavfilter/vf_idet.c
> 
> diff --git a/libavfilter/Makefile b/libavfilter/Makefile
> index 66d305d..5ab4e81 100644
> --- a/libavfilter/Makefile
> +++ b/libavfilter/Makefile
> @@ -67,6 +67,7 @@ OBJS-$(CONFIG_FREI0R_FILTER)                 += vf_frei0r.o
>  OBJS-$(CONFIG_GRADFUN_FILTER)                += vf_gradfun.o
>  OBJS-$(CONFIG_HFLIP_FILTER)                  += vf_hflip.o
>  OBJS-$(CONFIG_HQDN3D_FILTER)                 += vf_hqdn3d.o
> +OBJS-$(CONFIG_IDET_FILTER)                   += vf_idet.o
>  OBJS-$(CONFIG_LUT_FILTER)                    += vf_lut.o
>  OBJS-$(CONFIG_LUTRGB_FILTER)                 += vf_lut.o
>  OBJS-$(CONFIG_LUTYUV_FILTER)                 += vf_lut.o
> diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
> index 7715db3..f71246e 100644
> --- a/libavfilter/allfilters.c
> +++ b/libavfilter/allfilters.c
> @@ -75,6 +75,7 @@ void avfilter_register_all(void)
>      REGISTER_FILTER (GRADFUN,     gradfun,     vf);
>      REGISTER_FILTER (HFLIP,       hflip,       vf);
>      REGISTER_FILTER (HQDN3D,      hqdn3d,      vf);
> +    REGISTER_FILTER (IDET,        idet,        vf);

I find the name "idet" rather too elliptic.

>      REGISTER_FILTER (LUT,         lut,         vf);
>      REGISTER_FILTER (LUTRGB,      lutrgb,      vf);
>      REGISTER_FILTER (LUTYUV,      lutyuv,      vf);
> diff --git a/libavfilter/vf_idet.c b/libavfilter/vf_idet.c
> new file mode 100644
> index 0000000..772bfda
> --- /dev/null
> +++ b/libavfilter/vf_idet.c
> @@ -0,0 +1,276 @@
> +/*
> + * Copyright (C) 2012 Michael Niedermayer <michaelni at gmx.at>
> +*
> + * FFmpeg is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * FFmpeg is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License along
> + * with FFmpeg; if not, write to the Free Software Foundation, Inc.,
> + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
> + */
> +
> +#include "libavutil/cpu.h"
> +#include "libavutil/common.h"
> +#include "libavutil/pixdesc.h"
> +#include "avfilter.h"
> +
> +#undef NDEBUG
> +#include <assert.h>
> +
> +typedef struct {
> +    float interlace_threashold;
> +    float progressive_threashold;
> +
> +    AVFilterBufferRef *cur;
> +    AVFilterBufferRef *next;
> +    AVFilterBufferRef *prev;
> +    AVFilterBufferRef *out;
> +    int (*filter_line)(uint8_t *prev, uint8_t *cur, uint8_t *next,
> +                        int w);
> +
> +    const AVPixFmtDescriptor *csp;
> +} IDETContext;
> +
> +
> +static int filter_line_c(const uint8_t *a, const uint8_t *b, const uint8_t *c, int w)
> +{
> +    int x;
> +    int ret=0;
> +
> +    for(x=0; x<w; x++){
> +        ret += FFABS((*a++ + *c++) - 2 * *b++);
> +    }
> +
> +    return ret;
> +}
> +
> +static int filter_line_c_16bit(const uint16_t *a, const uint16_t *b, const uint16_t *c, int w)
> +{
> +    int x;
> +    int ret=0;
> +
> +    for(x=0; x<w; x++){
> +        ret += FFABS((*a++ + *c++) - 2 * *b++);
> +    }
> +
> +    return ret;
> +}
> +
> +static void filter(AVFilterContext *ctx)
> +{
> +    IDETContext *idet = ctx->priv;
> +    int y, i;
> +    int64_t alpha[2]={0};
> +    int64_t delta=0;
> +    static int p=0, t=0, b=0, u=0;
> +
> +    for (i = 0; i < idet->csp->nb_components; i++) {
> +        int w = idet->cur->video->w;
> +        int h = idet->cur->video->h;
> +        int refs = idet->cur->linesize[i];
> +        int df = (idet->csp->comp[i].depth_minus1 + 8) / 8;
> +
> +        if (i == 1 || i == 2) {
> +        /* Why is this not part of the per-plane description thing? */
> +            w >>= idet->csp->log2_chroma_w;
> +            h >>= idet->csp->log2_chroma_h;
> +        }
> +
> +        for (y = 2; y < h - 2; y++) {
> +            uint8_t *prev = &idet->prev->data[i][y*refs];
> +            uint8_t *cur  = &idet->cur ->data[i][y*refs];
> +            uint8_t *next = &idet->next->data[i][y*refs];
> +            alpha[ y   &1] += idet->filter_line(cur-refs, prev, cur+refs, w);
> +            alpha[(y^1)&1] += idet->filter_line(cur-refs, next, cur+refs, w);
> +            delta          += idet->filter_line(cur-refs,  cur, cur+refs, w);
> +        }
> +    }
> +#if HAVE_MMX
> +    __asm__ volatile("emms \n\t" : : : "memory");
> +#endif
> +
> +    if      (alpha[0] / (float)alpha[1] > idet->interlace_threashold){
> +        av_log(0, AV_LOG_INFO, "Interlaced, top field first\n");

There is a context available.

> +        t++;
> +    }else if(alpha[1] / (float)alpha[0] > idet->interlace_threashold){
> +        av_log(0, AV_LOG_INFO, "Interlaced, bottom field first\n");
> +        b++;
> +    }else if(alpha[1] / (float)delta    > idet->progressive_threashold){
> +        av_log(0, AV_LOG_INFO, "Progressive\n");
> +        p++;
> +    }else{
> +        av_log(0, AV_LOG_INFO, "Undetermined\n");
> +        u++;
> +    }
> +//     av_log(0,0, "t%d b%d p%d u%d\n", t,b,p,u);

This last line and the static local variables look like debug stuff that
should go away before commit.

Maybe use the result to fill the interlaced and top_field_first fields?

> +}
> +
> +static void return_frame(AVFilterContext *ctx)
> +{
> +}

This seems unused.

> +
> +static void start_frame(AVFilterLink *link, AVFilterBufferRef *picref)
> +{
> +    AVFilterContext *ctx = link->dst;
> +    IDETContext *idet = ctx->priv;
> +
> +    if (idet->prev)
> +        avfilter_unref_buffer(idet->prev);
> +    idet->prev = idet->cur;
> +    idet->cur  = idet->next;
> +    idet->next = picref;
> +
> +    if (!idet->cur)
> +        return;
> +
> +    if (!idet->prev)
> +        idet->prev = avfilter_ref_buffer(idet->cur, AV_PERM_READ);
> +
> +    avfilter_start_frame(ctx->outputs[0], avfilter_ref_buffer(idet->cur, AV_PERM_READ));
> +}
> +
> +static void end_frame(AVFilterLink *link)
> +{
> +    AVFilterContext *ctx = link->dst;
> +    IDETContext *idet = ctx->priv;
> +
> +    if (!idet->cur)
> +        return;
> +
> +    if (!idet->csp)
> +        idet->csp = &av_pix_fmt_descriptors[link->format];
> +    if (idet->csp->comp[0].depth_minus1 / 8 == 1)
> +        idet->filter_line = (void*)filter_line_c_16bit;
> +
> +    filter(ctx);
> +
> +    avfilter_draw_slice(ctx->outputs[0], 0, link->h, 1);
> +    avfilter_end_frame(ctx->outputs[0]);
> +}
> +
> +static int request_frame(AVFilterLink *link)
> +{
> +    AVFilterContext *ctx = link->src;
> +    IDETContext *idet = ctx->priv;
> +
> +    do {
> +        int ret;
> +
> +        if ((ret = avfilter_request_frame(link->src->inputs[0])))
> +            return ret;
> +    } while (!idet->cur);
> +
> +    return 0;
> +}
> +
> +static int poll_frame(AVFilterLink *link)
> +{
> +    IDETContext *idet = link->src->priv;
> +    int ret, val;
> +
> +    val = avfilter_poll_frame(link->src->inputs[0]);
> +
> +    if (val >= 1 && !idet->next) { //FIXME change API to not requre this red tape
> +        if ((ret = avfilter_request_frame(link->src->inputs[0])) < 0)
> +            return ret;
> +        val = avfilter_poll_frame(link->src->inputs[0]);
> +    }
> +    assert(idet->next || !val);
> +
> +    return val;
> +}
> +
> +static av_cold void uninit(AVFilterContext *ctx)
> +{
> +    IDETContext *idet = ctx->priv;
> +
> +    if (idet->prev) avfilter_unref_buffer(idet->prev);
> +    if (idet->cur ) avfilter_unref_buffer(idet->cur );
> +    if (idet->next) avfilter_unref_buffer(idet->next);
> +}
> +
> +static int query_formats(AVFilterContext *ctx)
> +{
> +    static const enum PixelFormat pix_fmts[] = {
> +        PIX_FMT_YUV420P,
> +        PIX_FMT_YUV422P,
> +        PIX_FMT_YUV444P,
> +        PIX_FMT_YUV410P,
> +        PIX_FMT_YUV411P,
> +        PIX_FMT_GRAY8,
> +        PIX_FMT_YUVJ420P,
> +        PIX_FMT_YUVJ422P,
> +        PIX_FMT_YUVJ444P,
> +        AV_NE( PIX_FMT_GRAY16BE, PIX_FMT_GRAY16LE ),
> +        PIX_FMT_YUV440P,
> +        PIX_FMT_YUVJ440P,
> +        AV_NE( PIX_FMT_YUV420P10BE, PIX_FMT_YUV420P10LE ),
> +        AV_NE( PIX_FMT_YUV422P10BE, PIX_FMT_YUV422P10LE ),
> +        AV_NE( PIX_FMT_YUV444P10BE, PIX_FMT_YUV444P10LE ),
> +        AV_NE( PIX_FMT_YUV420P16BE, PIX_FMT_YUV420P16LE ),
> +        AV_NE( PIX_FMT_YUV422P16BE, PIX_FMT_YUV422P16LE ),
> +        AV_NE( PIX_FMT_YUV444P16BE, PIX_FMT_YUV444P16LE ),
> +        PIX_FMT_YUVA420P,
> +        PIX_FMT_NONE
> +    };
> +
> +    avfilter_set_common_pixel_formats(ctx, avfilter_make_format_list(pix_fmts));
> +
> +    return 0;
> +}
> +
> +static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
> +{
> +    IDETContext *idet = ctx->priv;
> +    int cpu_flags = av_get_cpu_flags();
> +
> +    idet->csp = NULL;
> +
> +    idet->interlace_threashold   = 1.01;
> +    idet->progressive_threashold = 5;
> +
> +    if (args) sscanf(args, "%f:%f", &idet->interlace_threashold, &idet->progressive_threashold);
> +
> +    idet->filter_line = filter_line_c;
> +//     if (HAVE_SSSE3 && cpu_flags & AV_CPU_FLAG_SSSE3)
> +//         idet->filter_line = ff_idet_filter_line_ssse3;
> +//     else if (HAVE_SSE && cpu_flags & AV_CPU_FLAG_SSE2)
> +//         idet->filter_line = ff_idet_filter_line_sse2;
> +//     else if (HAVE_MMX && cpu_flags & AV_CPU_FLAG_MMX)
> +//         idet->filter_line = ff_idet_filter_line_mmx;
> +
> +    return 0;
> +}
> +
> +static void null_draw_slice(AVFilterLink *link, int y, int h, int slice_dir) { }
> +
> +AVFilter avfilter_vf_idet = {
> +    .name          = "idet",
> +    .description   = NULL_IF_CONFIG_SMALL("Interlace detect Filter."),
> +
> +    .priv_size     = sizeof(IDETContext),
> +    .init          = init,
> +    .uninit        = uninit,
> +    .query_formats = query_formats,
> +
> +    .inputs    = (const AVFilterPad[]) {{ .name       = "default",
> +                                    .type             = AVMEDIA_TYPE_VIDEO,
> +                                    .start_frame      = start_frame,
> +                                    .draw_slice       = null_draw_slice,
> +                                    .end_frame        = end_frame,
> +                                    .rej_perms        = AV_PERM_REUSE2, },
> +                                  { .name = NULL}},
> +
> +    .outputs   = (const AVFilterPad[]) {{ .name       = "default",
> +                                    .type             = AVMEDIA_TYPE_VIDEO,
> +                                    .poll_frame       = poll_frame,
> +                                    .request_frame    = request_frame, },
> +                                  { .name = NULL}},
> +};

Indentation is strange.

Regards,

-- 
  Nicolas George
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 198 bytes
Desc: Digital signature
URL: <http://ffmpeg.org/pipermail/ffmpeg-devel/attachments/20120404/46d08729/attachment.asc>


More information about the ffmpeg-devel mailing list